GIS Contribution for Marine Habitats Studies and Coastal Management. Application for the Rade De Toulon (Var, France, Occidental Mediterranean)

Jacques Denis (1) , Guillaume Bernard (2), Guirec Queffeulou (3)

(1) Laboratoire côtier - Centre IFREMER de Toulon-la Seyne (FR)
(2) GIS Posidonie - Marseille Luminy (FR)
(3) Toulon Provence Mediterranee TPM (FR)

Objective: the integrated coastal zones management requires various tools of planification adapted to the local problems. These tools requires a complete knowledge of the natural middle. The bay contract of Toulon (Var, France), currently in hand, is a significant example for the French Mediterranean of integrating data and information, needed by coastal managers, in managment plans. An inventory of natural marine resources was undertaken and lead to a marine habitats cartography ; almost 350 km2 are concerned.

Method: the marine habitats knowledge requires to collect, process and restore various data. Six streams of data were invested, namely ; ancient maps from bibliographical analysis, aerial photographs (shallow areas), side scan sonar (deeper areas) and data validation by scuba-diving and video camera surveys. The médiolittoral and upper stage of infralittoral biocenosis were also investigated. The same way of process was applied to the data set for obtaining a spatial information geographicaly, thematicaly and numericaly coherent, which could had been integrated in a GIS database.

Results: At the end of this study a general marine habitats cartography had been produced for the Toulon bay. The geographical distribution of each biocenosis has been translated in a GIS spatial theme. The metadata contains their physical vitality and, therefore, their sensitivity to disturbance caused, for exemple, by human activity as coastal development.

Conclusion: the product obtained, had been widely diffused to the local actors, it contributes to a better knowledge of the marine environment characteristics of the Toulon Bay ; by bringing new decision tools for locals managers, it prooved its high utility for integrated coastal managment, for exemple by optimizing marine biocenosis monitoring.

Thanks to the GIS database and to geographical information which it contains, carrying out conservation measures and safeguards for marine environment could have been argumented ; A marine protected area project is actually in hand.